The present disclosure relates to a drive transmission device for transmitting a rotational drive force to a rotary body, and a sheet conveying device and an image forming apparatus provided with the same.
Conventionally, a drive transmission device is known which transmits a rotational drive force to a rotary body. The drive transmission device transmits a rotational drive force to a conveyor roller pair of an image forming apparatus. The conveyor roller pair conveys a sheet in a predetermined direction. Further, sun gears and planetary gears are used in the drive transmission device. In this technique, two sun gears are provided and rotating directions of the conveyor rollers are controlled by selectively fixing the rotation of either one of the sun gears.